<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    const year = parseInt(prompt("请输入年份"))
    if (year % 4 === 0 && year % 100 !== 0 || year % 400 === 0) {
        alert(`${year}闰年`)
    } else {
        alert(`${year}平年`)
    }
</script>
</body>
</html>